/* px en rem 等长度单位演示 */



html{
    font-size: 62.5%;

}

body{
    font-size: 10px;
}






.value_px{
    font-size: 32px;
}

.value_en{
    font-size: 2em;
}

.value_rem{
    font-size: 2rem;
}

/* 颜色值 */
.color_name
{
    color: red;
}
.color_hex{
    color: #00ff00;
}
.color_fun{
    color: rgb(0,0,255);
}
/* 图片函数url */
.img_url{
    width: 262px;
    height: 70px;
    background-image: url("qq_logo.png");
    font-weight: bolder;
}
/* 常见字体样式属性 */

.font_demo{
    /* font:400; */
    color: red;
    font-family:微软雅黑  sans-serif;
    font-size: 2em;
    font-style: italic;
    font-weight: normal;
}

/* 常见文本样式属性 */
.text_demo{
    font-size: 2em;
    border: 1px solid black;
    width: 50rem;
    height: 10rem;
    text-align: left;
    line-height: 10rem;
    text-decoration: underline;
    text-indent: 3rem;
    letter-spacing: 1rem;
    word-spacing: 2rem;
}

/* 列表样式属性 */
ul{
    font-size: 2rem;
}
.list_demo1{
    list-style: circle inside;
}
.list_demo2{
    list-style: none;
}
.list_demo3{
    list-style-image: url("qq_logo.png");
    list-style-type: none;
    list-style-position: inside;

}
.list_demo4{
    list-style: none url("qq_logo.png") inside;
}

/* 背景样式属性 */
.bg_box{
    border: 1px solid red;
    width: 40rem;
    height: 20rem;

}

.bg_demo1{
    background-color: coral;
    

}
.bg_demo2{
    background-color: url("qq_logo.png");

}

.bg_demo3{
    background-image: url("qq_logo.png");
    /* background-repeat: no-repeat; */
    background-repeat: no-repeat-y;

}
.bg_demo4{
    background-image: url(qq_logo.png);
    background-repeat:no-repeat   ;
    background-position: right bottom;
}
.bg_demo5{
    background-image: url(qq_logo.png);
    background-repeat: no-repeat;
    background-position: top right;
    background-attachment: fixed;
}

.bg_demo6{
    background-color: #c2f3c2 url(qq_logo.png) repeat-x top right fixed;
}

/* 表格样式 */
.table_demo{
    font-size: 2rem;
    border: 1px solid #000;
    width: 70%;
    margin: 0 auto;
    table-layout: fixed;
    caption-side: top;
    border-collapse: collapse;
    /* border-collapse: separate; */
    border-spacing: 10px;
    empty-cells: show;
}


.table_demo caption{
    font-size: 2.5rem;
}
.table_demo th, .table_demo td{
    border-top: 1px  solid #000;
    border-bottom: 1px  solid #000;
    text-align: center;
}

.table_demo thead{
    background-color:     rgb(187, 39, 39);
    color: white;
}
.table_demo tbody tr:hover{
    background: #d8e61d;
    cursor: pointer;
}

.table_demo tfoot td{
    text-align: right;
    padding-right: 2rem;
}

/* 表单样式 */
.form_demo{
    font-size: 1rem;
    border: 1px solid seagreen;
    background: #fff;
    width: 35rem;
    height: 25rem;
    text-align: center;
}

.form_demo input[type="text"],.form_demo input[type="password"] {
    border-left: 0;
    border-right: 0;
    border-top: 0;
    border-bottom: 1px solid #000;
    width: 200px;
    height: 39px;
    padding-left: 44px;

}

.form_demo #username{
    background: #fff no-repeat top left;
}

.form_demo #pwd{
    background: #fff  no-repeat top left; 
 }


 .form_demo[type="submit"]{
     width: 100px;
     height: 38px;
     background-color: rgb(156, 69, 255);
     border: 1px dashed #2e5bec;
     border-radius: 10px;
     color: aliceblue;
     letter-spacing: 10px;
 }



